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The "No EQ" DSO Challenge!


JGM1971

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11 hours ago, happy-kat said:

You did very well Susan to get good star shapes taking those images hand held. The window doesn't appear to have had a noticeable detrimental effect.

You might like to look through the image submissions to challenge number 8 as there are quite a few in there that were taken on static mounts. This thread the images have been taken on motorised tracking mounts but which aren't EQ.

Many thanks :)

I am new to the astro bit of photography, only been experimenting since this January 2018.

I have "a few" manual Nikkor lenses from "back in the day" when my film camera was a Nikkormat FTn (and then a F2 Photomic from my step-father). 

Having taken a few shots of the moon now and again I decided to have a go at some longer exposures... and to my great surprise found that I was getting sometimes up into the thousand+ number of stars - which is a thing as here in West London as one can only see a dozen or so on a good night, usually less.

Still experimenting with how to process. The only "special" thing with the image is that I did use a IDAS-D1 Light Pollution Suppression Filter (a FLO special offer), otherwise it's straight forward photo equipment.

I hadn't realised about this thread being for tracking... I interpreted no-EQ as static :)

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6 hours ago, Filroden said:

What I love about this is that you've taken a really sharp widefield image with hand-held (albeit supported). There's even star colour data in the image though you really need to push the processing hard to bring it out. I hit it hard with the star colour hammer (hope you don't mind) to show it's in the image (blues have gone a little purple):

180507-Spica-in-Virgo-mag10-4-stack-DSC_2829_32-full-1.thumb.jpg.8c0e2641fd7560fc98f1d1db1b13c182.jpg

With that nice field of view you might want to try some other areas and capture some clusters.

WOW, that is awesome. I can't imagine where you got all that colour information from, particually as it's a JPEG!!!

Very happy for your enhancment. Where do I find a "star colour hammer"?

The view with the 85mm is 24x16 degrees, on the FX D800 sensor giving a nominal pixel size of 12 arc-seconds. However that is the RGGB bayer, and all that so pragmatically the smallest is more like 24... and then with all the atmospherics at least double that and then add a bit more!

I have a few more images... this was one of the better ones and taken a few nights ago.

Main thing is that in all my images I see a very sharp cut-off for magnitude. If I poke around in the above for example I can discern a few into the 10s, but that's it.  The background "noise" is significant, even with stacking, DSLR sensor noise reduction, and DxO Prime NR.

The best I have got is magnitude 14, with my 500mm f/8 Tamron mirror lens and a stack of seven 15 second tracking shots (longest exposure I could do before the stars started to trail).

My images are semi-opertunity since I only have a small view south from a window. Nowhere local to set up although I have plans/hopes to get a bit away from London sometime and see some real stars :)

I am having a go at uploading the full TIFF file... it's taking a while :)

180507-Spica-in-Virgo-mag10-4-stack-DSC_2829_32-full-1.tif

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The thread was setup to show what could be achieved when using a mount that tracked but was not equatorial. AltAz mounts track (when motorised) in tiny left right up down movements are are often mounts people might start off with and then get a desire to taste taking images and are hit with the but it is not equatorial so it is no use. Whilst motorised equatorial is the best type of mount for imaging as the Earth's rotation is followed correctly (the better the mount the better the tracking as not all mounts are equal) imaging can be done within the limitations of a tracking altaz mount which this threads sets out to show and share.

If possible I would suggest you try adding some flats to your imaging adventure as these would help with any vignetting seen. I use my 7 inch tablet running the app lightbox to take my flats as that is what I have available to use.  Generally it is best to turn off in camera noise reduction as it can eat stars. Do you have an intervalometer you could use, it could bang out say 50+ images as you hold the camera to the window and DSS deals with aligning your images and then just crop the stacking artifacts around the edges out in processing.

Old manual lenses are lovely the focuser is I've found generally buttery smooth.

I bet your window is kept super clean.

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48 minutes ago, susan-parker said:

WOW, that is awesome. I can't imagine where you got all that colour information from, particually as it's a JPEG!!!

Very happy for your enhancment. Where do I find a "star colour hammer"?

 

I’m not sure how real the colours are but each of your stars showed very subtle differences in their RGB values but they need to be stretched to extremes to show it. I have an action in Photoshop that increases star colour. I think it takes colour in the halo and maps it back into the white core. I also pushed vibrancy and saturation to make it easier to see.

in reality, you’ll get a better result from the original image. 

I think the magnitude limit is a function of aperture and total integration time so to go deeper you need to stack many more subs.

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23 hours ago, Filroden said:

I’m not sure how real the colours are but each of your stars showed very subtle differences in their RGB values but they need to be stretched to extremes to show it. I have an action in Photoshop that increases star colour. I think it takes colour in the halo and maps it back into the white core. I also pushed vibrancy and saturation to make it easier to see.

in reality, you’ll get a better result from the original image. 

I think the magnitude limit is a function of aperture and total integration time so to go deeper you need to stack many more subs.

Ah, okay I will see how creative I can be :)

As to magnitude; the issue is that there is significant background, so I rapidly hit a photon-wall!

Attached is one of the four "as shot" (but JPEG'ed) frames.

DSC_2830_DxO.jpg

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On 5/11/2018 at 21:04, Filroden said:

I have an action in Photoshop that increases star colour. I think it takes colour in the halo and maps it back into the white core.

Is that a plugin or a scripted action please?

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11 hours ago, susan-parker said:

Attached is one of the four "as shot" (but JPEG'ed) frames.

As someone has already suggested, taking flats would probably offer the single biggest improvement to the image. You have some significant vignetting in the image which flats will deal with. I used to stress about taking flats but found they were very easy on a sunny day. Just aim your camera/lens at a part of the sky away from the sun and put 3 or 4 sheets of plain white paper over the lens. Find an exposure that generates a histogram that peaks about 50%. You may need more or less paper to control this.

Once you've flattened the images (which can be done in DSS and other stacking software) the light pollution will show a more even gradient (more linear rather than circular) and will be easier to remove.

That said, given how much vignetting and light pollution you're fighting, I'm even more impressed with your result :)

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Hi All! That was an unbelivable nice night here. My Celesteon Nexstar 8" SE with alt-az mount was ready to watch the sky. I took again pics, over 25mm eyepiece with my Huawei P10 smartphone, in monochrome mode. ISO 1000, 15 sec exposition pro object. Swan-nebula, Lagun-nebula, Trifid - nebula. There is no edit on the pictures, only cut and rotate with Lightroom app. 

IMG_20180513_085852.jpg

IMG_20180513_090018.jpg

IMG_20180513_183949.jpg

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Never thought I could post here when I read this thread a while back, just realised I can finally contribute!

I recently acquired a SW 300 goto dob and on a really clear night the whirlpool galaxy was so bright in my eyepiece, so I ran in and grabbed my camera for a quick snap. I think this is a single 30 second light at iso 6400, with details really stretched out on the iPad 

117F0541-BB04-47E3-A2C7-F5C48A20F6D7.jpeg

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Hi All! Finally I tried to stack few pictures in DSS, only to get some experience about that. My object is Messier 4, I took 5 x 5sec pic in raw mode with my Huawei P10, 25 mm eyepiece (80x magnification) with my Celestron Nexstar 8" SCT. On my laptop it looks great, it shows the young blue and the older red stars. Interesting, but on my phone its only hard yellow, all the stars in the cluster. 

stackedPSMessier4.png

Edited by smisy
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At last november I bought a G3 Orion deepsky cam, but in the winter I didnt use that. Because of the cold I dont like to take picturs with the cam + laptop combination. Anyway, I took a picture about the center on Orion nebula, the Trapesium. Its much better, as my smartphone pictures, but with the cam I have very small field, because of my 2000 mm focal lenght.

 

joleszaz.png

Edited by smisy
edited because of the wrong file format
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8 hours ago, Lokifish said:

Afocal DSO shots, with a cellphone on an alt/az. I can hear the screams of "you can't do that" from here.  :thumbsup:

And alt-az mount... Yes, I heared that, its impossible. This is exactly the reason,  why I do it ?

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This is my first post when I afraid, my english is not enough to explane something, huh, so: I just tried to use the "light painting" - mode on my Huawei P10, but not to see  that, how the stars make lines on the sky. I used this function with my Celestron 8" SCT on alt-az mount, with following. Its interesting, because it makes pictures in every 3 second and stack them in real time! Interesting to see that, how the stars comes up from the dark. I made a screen video about that, how its going, enjoy! Video 1:Alpha Lyrae, video 2:  Ring nebula

SVID_20180518_235812.mp4

SVID_20180519_000312.mp4

IMG_20180518_235850.jpg

IMG_20180519_000206.jpg

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4 hours ago, smisy said:

The different of Huawei P10 color and monochrome camera. Ring - nebula, ISO 3200, 10 sec exposition, Celestron Nexstar 8", 25 mm eyepiece. 

 

 

You can see more stars in the mono one. Have you tried using it as a luminance layer over the colour version?

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1 hour ago, Stub Mandrel said:

You can see more stars in the mono one. Have you tried using it as a luminance layer over the colour version?

You mean, to stack them somehow? I didn't try that.

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From the 15th May (at 21:55 GMT), stars below Libra.
Spica middle top, y-Hydra middle bottom, and Kraz (from Corvus) bottom left.
Stack of 9 shots... hand held.
Colours are "interesting" from the Bayer interpolation and levels boosting.
Two images: full frame scaled to 1800 pix wide, and a 1to1 pixel crop from the centre of the original frame (63 Virgo, 61 Virgo, and HIP 65183 making a triangle in the center); plus full frame 16bpc TIFF file.
Processed in Photoshop.
Each pixel is c. 12 arc-seconds. Stars visable down to magnitude 10.
Nikon D800 with Nikkor 85mm f/2.0 at f/2.8, 9 x 2.5 seconds, ISO 800. IDAS D1.

180515-stack9frames-Spica+y-Hydra+Kraz-stars-1c-1800.jpg

180515-stack9frames-Spica+y-Hydra+Kraz-stars-1c-crop-1800x1800.jpg

180515-stack9frames-Spica+y-Hydra+Kraz-stars-1c.tif

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